mtx_enter(lock, type) becomes:
mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)
similarily, for releasing a lock, we now have:
mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.
The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.
Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:
MTX_QUIET and MTX_NOSWITCH
The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:
mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.
Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.
Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.
Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.
Finally, caught up to the interface changes in all sys code.
Contributors: jake, jhb, jasone (in no particular order)
usb_ethersubr.c. This module maintains two queues for packets which
are each protected with one mutex. These are all the changes I can
do for now. Removing the USBD_NO_TSLEEP flag doesn't work yet: when
I tried it, the system would usually freeze up after a NIC had been
operating for a while. The usb_ethersubr module itself ought to
go away; this is the next thing I need to test.
uhci_check_intr() routine needs to be more careful about deciding when
the end of a transfer has been detected.
This allows me to remove the nasty workaround code from if_aue and if_cue.
Receive performance is now much better for these adapters (500KB/sec
vs. 350KB/sec).
Also removed unused KUE_CUTOFF define from if_kuereg.h.
Submitted by: Lennart Augustsson
Reviewed by: n_hibma
- Sync ohci, uhci and usbdi modules with NetBSD in order to obtain the
following improvements:
o New USBD_NO_TSLEEP flag can be used in place of UQ_NO_TSLEEP
quirk. This allows drivers to specify busy waiting only for
certain transfers (namely control transfers for reading/writing
registers and stuff).
o New USBD_FORCE_SHORT_XFER flag can be used to deal with
devices like the ADMtek Pegasus that sense the end of bulk OUT
transfers in a special way (if a transfer is exactly a multiple
of 64 bytes in size, you need to send an extra empty packet
to terminate the transfer).
o usbd_open_pipe_intr() now accepts an interval argument which
can be used to change the rate at which the interrupt callback
routine is invoked. Specifying USBD_DEFAULT_INTERVAL uses the
value specified in the device's config data, but drivers can
override it if needed.
- Change if_aue to use USBD_FORCE_SHORT_XFER for packet transmissions.
- Change if_aue, if_kue and if_cue to use USBD_NO_TSLEEP for all
control transfers. We no longer force the non-tsleep hack for
bulk transfers since these are done asynchronously anyway.
- Removed quirk entry fiddling from if_aue and if_kue since we don't
need it anymore now that we have the USBD_NO_TSLEEP flag.
- Tweak ulpt, uhid, ums and ukbd drivers to use the new arg to
usbd_open_pipe_intr().
- Add a flag to the softc struct in the ethernet drivers to indicate
when a device has been detached, and use this flag to perform
tests to prevent the drivers from trying to do control transfers
if this is the case. This is necessary because calling if_detach()
with INET6 enabled will eventually result in a call to the driver's
ioctl() routine to delete the multicast groups on the interface,
which will result in attempts to perform control transfers. (It's
possible this also happens even without INET6 support enabled.) This
is pointless since we know that if the detach method has been called,
the hardware has been unplugged.
- Changed watchdog timeout routines to just call the driver init routines
to initialize the device states without trying to close and re-open the
pipes. This is partly because we don't want to frob things at interrupt
context, but also because this doesn't seem to work right and I don't
want to panic the system just because a USB device may have stopped
responding.
- Fix aue_rxeof() to be a little smarter about detecting when a double
transfer is needed. Unfortunately, the design of the chip makes it hard
to get this exactly right. Hopefully, this will go away once either
Nick or Lennart finds the bug in the uhci driver that makes this ugly
hack necessary.
- Also sync usbdevs with NetBSD.
certain PHY addresses in aue_miibus_readreg(). Not all adapters based
on the Pegasus chip may have their PHYs wired for the same MII bus
addresses: the logic that I used for my ADMtek eval board might not
apply to other adapters, so make sure to only use it if this is really
an ADMtek eval board (check the vendor/device ID).
This will hopefully make the LinkSys USB100TX adapter work correctly.
USB ethernet chip. Adapters that use this chip include the LinkSys
USB100TX. There are a few others, but I'm not certain of their
availability in the U.S. I used an ADMtek eval board for development.
Note that while the ADMtek chip is a 100Mbps device, you can't really
get 100Mbps speeds over USB. Regardless, this driver uses miibus to
allow speed and duplex mode selection as well as autonegotiation.
Building and kldloading the driver as a module is also supported.
Note that in order to make this driver work, I had to make what some
may consider an ugly hack to sys/dev/usb/usbdi.c. The usbd_transfer()
function will use tsleep() for synchronous transfers that don't complete
right away. This is a problem since there are times when we need to
do sync transfers from an interrupt context (i.e. when reading registers
from the MAC via the control endpoint), where tsleep() us a no-no.
My hack allows the driver to have the code poll for transfer completion
subject to the xfer->timeout timeout rather that calling tsleep().
This hack is controlled by a quirk entry and is only enabled for the
ADMtek device.
Now, I'm sure there are a few of you out there ready to jump on me
and suggest some other approach that doesn't involve a busy wait. The
only solution that might work is to handle the interrupts in a kernel
thread, where you may have something resembling a process context that
makes it okay to tsleep(). This is lovely, except we don't have any
mechanism like that now, and I'm not about to implement such a thing
myself since it's beyond the scope of driver development. (Translation:
I'll be damned if I know how to do it.) If FreeBSD ever aquires such
a mechanism, I'll be glad to revisit the driver to take advantage of
it. In the meantime, I settled for what I perceived to be the solution
that involved the least amount of code changes. In general, the hit
is pretty light.
Also note that my only USB test box has a UHCI controller: I haven't
I don't have a machine with an OHCI controller available.
Highlights:
- Updated usb_quirks.* to add UQ_NO_TSLEEP quirk for ADMtek part.
- Updated usbdevs and regenerated generated files
- Updated HARDWARE.TXT and RELNOTES.TXT files
- Updated sysinstall/device.c and userconfig.c
- Updated kernel configs -- device aue0 is commented out by default
- Updated /sys/conf/files
- Added new kld module directory
